I'm sure this topic has been beaten to death but since I recently shifted from iPhone to Blackberry curve and seem to have an opinion contrary to popular one, I'm going to post it here. I owned my iPhone original for more than 2 years (bought it the first day iPhone was released for $599) so I think I can safely comment on its operation with an air of authoritative user. The Blackberry, however, has been with me for only a couple of weeks so take those comments with a grain of salt. Here are my observations:
1. Web Browsing: iPhone wins hands down. I cannot browse to save my life on a BB. If the website is not tailored for mobile devices don't even think about trying to access it on BB. One advantage with BB is that javascript are supported.
2. Applications: iPhone definitely has more of these. Having said that, for me it didn't matter much because I found all the apps I was using on my iPhone available for BB. add to that the availability of Google Voice app on BB, there is no clear winner here and the result will depend on particular user tastes.
3. Multitasking: BB is the winner here. no multitasking support on iPhone yet. Its nice to lock your phone and still get your IM notifications while staying online.
4. Streaming content: BB plays most of the streaming content online without any issues. Unless you have a specific app installed on iPhone (e.g. Pandora) you mostly cannot click on the link online and expect the content to start streaming directly. My phone uses EDGE network so videos do take some time to buffer before they play.
5. Form factor: Both the phones feel good in hand but BB seems more sturdy in construction.
6. Basic Phone: BB is a pretty good phone. Nice loud speakerphone and the basic phone features are easy to access and use. iPhone is a good music player but not a great phone. Even though the latest phones have added voice dialling, the speakerphone is too weak to be able to used for a decent phone conversation. Further, accessing functions like mute, hold is tough without taking the phone off your ear and looking at it.
7. Battery life: BB battery is lasting me for about 2.5 days with light browsing, 3 push email accounts, 2 minutes of GPS use and about 2 hours of phone use. I had to charge iPhone everyday.
8. Replacement battery: iPhone needs to be sent to apple (100 bucks total) for replacing a battery. One is better off buying a new phone depending on the state of his/her contract. BB batteries are user replaceable.
9. Music Playback: I haven't copied much content onto my BB yet so can't comment on this, but I suspect iPhone will beat BB in this category because of its iPod interface. BB is supposed to sync with your iTunes library though.
10. Camera: My BB has a 3.2MP camera with flash. Latest iPhone has a 2MP camera. BB pictures in darker environments seem to have a non-natural hue to them. My original godPhone had only 1MP camera so I cant comment on new iPhone's camera quality.
11. GPS: My original iPhone used cell tower triangulation for GPS, BB curve has a built in GPS and integrates seamlessly with Google Maps. I installed a free third-party app for turn-by turn navigation and things are working fine. I have not heard any complaints about the GPS from my iPhone 3G-S user friends either.
I have intentionally left out the enterprise email facility of BB since I did not get my phone for that use and have not had a chance to experience it on the iPhone either.
No points for guessing what my phone is going to be for the next one year. Other users out there: would love to know what you think : ) .